Extreme Anisotropy of the g -Factor in Quantum Wires

Spin quantum beats of free-electron Larmor precession are measured by time-resolved photoluminescence spectroscopy and yield an extreme anisotropy of the electron Landé g -factor in quantum wires. The g -factor changes from 0.56 along the wires to approximately 0 perpendicular to the wires. The experimental results are in good agreement with an estimate according to k · p theory.